diff --git a/handshake.go b/handshake.go
index ce7f9e7..0e008c4 100644
--- a/handshake.go
+++ b/handshake.go
@@ -54,9 +54,9 @@ func (m *clientHelloMsg) unmarshal(data []byte) bool {
 }
 
 //go:linkname makeClientHello crypto/tls.(*Conn).makeClientHello
-func makeClientHello(c *trsconn) (*clientHelloMsg, *ecdh.PrivateKey, error)
+func makeClientHello(c *_trsconn) (*clientHelloMsg, *ecdh.PrivateKey, error)
 
-func (c *trsconn) makeClientHello() (*clientHelloMsg, *ecdh.PrivateKey, error) {
+func (c *_trsconn) makeClientHello() (*clientHelloMsg, *ecdh.PrivateKey, error) {
 	return makeClientHello(c)
 }
 
@@ -126,20 +126,20 @@ type sessionState struct {
 }
 
 //go:linkname loadSession crypto/tls.(*Conn).loadSession
-func loadSession(c *trsconn, hello *clientHelloMsg) (
+func loadSession(c *_trsconn, hello *clientHelloMsg) (
 	session *sessionState, earlySecret, binderKey []byte, err error,
 )
 
-func (c *trsconn) loadSession(hello *clientHelloMsg) (
+func (c *_trsconn) loadSession(hello *clientHelloMsg) (
 	session *sessionState, earlySecret, binderKey []byte, err error,
 ) {
 	return loadSession(c, hello)
 }
 
 //go:linkname clientSessionCacheKey crypto/tls.(*Conn).clientSessionCacheKey
-func clientSessionCacheKey(c *trsconn) string
+func clientSessionCacheKey(c *_trsconn) string
 
-func (c *trsconn) clientSessionCacheKey() string {
+func (c *_trsconn) clientSessionCacheKey() string {
 	return clientSessionCacheKey(c)
 }
 
@@ -177,12 +177,12 @@ func transcriptMsg(msg handshakeMessage, h transcriptHash) error
 const clientEarlyTrafficLabel = "c e traffic"
 
 //go:linkname quicSetWriteSecret crypto/tls.(*Conn).quicSetWriteSecret
-func quicSetWriteSecret(c *trsconn, level tls.QUICEncryptionLevel, suite uint16, secret []byte)
+func quicSetWriteSecret(c *_trsconn, level tls.QUICEncryptionLevel, suite uint16, secret []byte)
 
 //go:linkname readHandshake crypto/tls.(*Conn).readHandshake
-func readHandshake(c *trsconn, transcript transcriptHash) (any, error)
+func readHandshake(c *_trsconn, transcript transcriptHash) (any, error)
 
-func (c *trsconn) readHandshake(transcript transcriptHash) (any, error) {
+func (c *_trsconn) readHandshake(transcript transcriptHash) (any, error) {
 	return readHandshake(c, transcript)
 }
 
@@ -193,9 +193,9 @@ type serverHelloMsg struct {
 }
 
 //go:linkname sendAlert crypto/tls.(*Conn).sendAlert
-func sendAlert(c *trsconn, err alert) error
+func sendAlert(c *_trsconn, err alert) error
 
-func (c *trsconn) sendAlert(err alert) error {
+func (c *_trsconn) sendAlert(err alert) error {
 	return sendAlert(c, err)
 }
 
@@ -208,9 +208,9 @@ const (
 )
 
 //go:linkname pickTLSVersion crypto/tls.(*Conn).pickTLSVersion
-func pickTLSVersion(c *trsconn, serverHello *serverHelloMsg) error
+func pickTLSVersion(c *_trsconn, serverHello *serverHelloMsg) error
 
-func (c *trsconn) pickTLSVersion(serverHello *serverHelloMsg) error {
+func (c *_trsconn) pickTLSVersion(serverHello *serverHelloMsg) error {
 	return pickTLSVersion(c, serverHello)
 }
 
@@ -293,7 +293,7 @@ func (hs *clientHandshakeState) handshake() error {
 // writeHandshakeRecord writes a handshake message to the connection and updates
 // the record layer state. If transcript is non-nil the marshalled message is
 // written to it.
-func (c *trsconn) writeHandshakeRecord(msg handshakeMessage, transcript transcriptHash) (int, error) {
+func (c *_trsconn) writeHandshakeRecord(msg handshakeMessage, transcript transcriptHash) (int, error) {
 	c.out.Lock()
 	defer c.out.Unlock()
 
@@ -305,10 +305,12 @@ func (c *trsconn) writeHandshakeRecord(msg handshakeMessage, transcript transcri
 		transcript.Write(data)
 	}
 
-	return writeRecordLocked(c, recordTypeHandshake, data)
+	return c.writeRecordLocked(recordTypeHandshake, data)
 }
 
-func (c *trsconn) clientHandshake(ctx context.Context) (err error) {
+func (cout *trsconn) clientHandshake(ctx context.Context) (err error) {
+	c := (*_trsconn)(unsafe.Pointer(cout))
+
 	if c.config == nil {
 		c.config = defaultConfig()
 	}
@@ -390,7 +392,7 @@ func (c *trsconn) clientHandshake(ctx context.Context) (err error) {
 
 	if c.vers == tls.VersionTLS13 {
 		hs := &clientHandshakeStateTLS13{
-			c:           c,
+			c:           cout,
 			ctx:         ctx,
 			serverHello: serverHello,
 			hello:       hello,
@@ -405,7 +407,7 @@ func (c *trsconn) clientHandshake(ctx context.Context) (err error) {
 	}
 
 	hs := &clientHandshakeState{
-		c:           c,
+		c:           cout,
 		ctx:         ctx,
 		serverHello: serverHello,
 		hello:       hello,
diff --git a/terasu.go b/terasu.go
index 2b8cbf4..c504411 100644
--- a/terasu.go
+++ b/terasu.go
@@ -7,7 +7,6 @@ import (
 
 // Use terasu in this TLS conn
 func Use(conn *tls.Conn) *tls.Conn {
-	trsConn := (*trsconn)(unsafe.Pointer(conn))
-	trsConn.handshakeFn = trsConn.clientHandshake
-	return (*tls.Conn)(unsafe.Pointer(trsConn))
+	(*_trsconn)(unsafe.Pointer(conn)).handshakeFn = (*trsconn)(conn).clientHandshake
+	return conn
 }
diff --git a/terasu_test.go b/terasu_test.go
index dfaea3e..7300091 100644
--- a/terasu_test.go
+++ b/terasu_test.go
@@ -8,7 +8,7 @@ import (
 	"testing"
 )
 
-func TestHTTPDialTLS(t *testing.T) {
+func TestHTTPDialTLS13(t *testing.T) {
 	cli := http.Client{
 		Transport: &http.Transport{
 			DialTLS: func(network, addr string) (net.Conn, error) {
@@ -38,3 +38,35 @@ func TestHTTPDialTLS(t *testing.T) {
 	}
 	t.Log(string(data))
 }
+
+func TestHTTPDialTLS12(t *testing.T) {
+	cli := http.Client{
+		Transport: &http.Transport{
+			DialTLS: func(network, addr string) (net.Conn, error) {
+				conn, err := net.Dial("tcp", "18.65.159.2:443")
+				if err != nil {
+					return nil, err
+				}
+				t.Log("net.Dial succeeded")
+				return Use(tls.Client(conn, &tls.Config{
+					ServerName:         "huggingface.co",
+					InsecureSkipVerify: true,
+					MaxVersion:         tls.VersionTLS12,
+				})), nil
+			},
+		},
+	}
+	resp, err := cli.Get("https://huggingface.co/")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatal("status code:", resp.StatusCode)
+	}
+	data, err := io.ReadAll(resp.Body)
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Log(string(data))
+}
diff --git a/tls.go b/tls.go
index 306b477..e5092e1 100644
--- a/tls.go
+++ b/tls.go
@@ -57,9 +57,11 @@ type halfConn struct {
 	trafficSecret []byte                  // current TLS 1.3 traffic secret
 }
 
-// A trsconn represents a secured connection.
-// It implements the net.trsconn interface.
-type trsconn struct {
+type trsconn tls.Conn
+
+// A _trsconn represents a secured connection.
+// It implements the net._trsconn interface.
+type _trsconn struct {
 	// constant
 	conn        net.Conn
 	isClient    bool
@@ -139,12 +141,12 @@ type trsconn struct {
 var outBufPool sync.Pool
 
 //go:linkname tlsWriteRecordLocked crypto/tls.(*Conn).writeRecordLocked
-func tlsWriteRecordLocked(c *trsconn, typ recordType, data []byte) (int, error)
+func tlsWriteRecordLocked(c *_trsconn, typ recordType, data []byte) (int, error)
 
 //go:linkname maxPayloadSizeForWrite crypto/tls.(*Conn).maxPayloadSizeForWrite
-func maxPayloadSizeForWrite(c *trsconn, typ recordType) int
+func maxPayloadSizeForWrite(c *_trsconn, typ recordType) int
 
-func (c *trsconn) maxPayloadSizeForWrite(typ recordType) int {
+func (c *_trsconn) maxPayloadSizeForWrite(typ recordType) int {
 	return maxPayloadSizeForWrite(c, typ)
 }
 
@@ -162,16 +164,16 @@ func (hc *halfConn) encrypt(record, payload []byte, rand io.Reader) ([]byte, err
 func rand(c *tls.Config) io.Reader
 
 //go:linkname write crypto/tls.(*Conn).write
-func write(c *trsconn, data []byte) (int, error)
+func write(c *_trsconn, data []byte) (int, error)
 
-func (c *trsconn) write(data []byte) (int, error) {
+func (c *_trsconn) write(data []byte) (int, error) {
 	return write(c, data)
 }
 
 //go:linkname flush crypto/tls.(*Conn).flush
-func flush(c *trsconn) (int, error)
+func flush(c *_trsconn) (int, error)
 
-func (c *trsconn) flush() (int, error) {
+func (c *_trsconn) flush() (int, error) {
 	return flush(c)
 }
 
@@ -183,15 +185,15 @@ func (hc *halfConn) changeCipherSpec() error {
 }
 
 //go:linkname sendAlertLocked crypto/tls.(*Conn).sendAlertLocked
-func sendAlertLocked(c *trsconn, err alert) error
+func sendAlertLocked(c *_trsconn, err alert) error
 
-func (c *trsconn) sendAlertLocked(err alert) error {
+func (c *_trsconn) sendAlertLocked(err alert) error {
 	return sendAlertLocked(c, err)
 }
 
 // writeRecordLocked writes a TLS record with the given type and payload to the
 // connection and updates the record layer state.
-func writeRecordLocked(c *trsconn, typ recordType, data []byte) (int, error) {
+func (c *_trsconn) writeRecordLocked(typ recordType, data []byte) (int, error) {
 	if c.quic != nil {
 		return tlsWriteRecordLocked(c, typ, data)
 	}